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EPA reverses decision on pet collar chemical

Organophosphate pesticide tetrachlorvinphos can stay in flea and tick collars

by Britt E. Erickson
September 20, 2023


The US Environmental Protection Agency is backtracking on a decision it made last year to ban the organophosphate pesticide tetrachlorvinphos (TCVP) in pet collars used to control fleas, ticks, and other pests. In a revised human health risk assessment released Sept. 19, the agency now says such collars do not pose unacceptable health risks to children.

Chemical structure of tetrachlorvinphos.

The EPA used data submitted by Hartz, the manufacturer of pet collars containing TCVP, to justify its decision. The new data include amounts of TCVP residue that come off a collar when it is removed from packaging, stretched, and put on a pet. The data also include amounts on the pet’s fur after the collar is worn.

In previous assessments, the EPA found that children could be exposed to dangerous levels of TCVP through pet fur. Organophosphate pesticides are neurotoxic and harmful to developing brains.

The EPA is proposing several mitigation measures in exchange for the continued use of TCVP, including a requirement for enhanced reporting and TCVP sales data in pet products.

The Natural Resources Defense Council (NRDC), an environmental group that petitioned the EPA to ban pet products containing TCVP in 2009, says it is disappointed in the EPA’s updated assessment. The group says the agency relied on flawed data supplied by the pesticide industry without outside scientific review.

“From a public health perspective, we are super concerned that EPA is issuing revised assessments based on unvalidated data from industry on organophosphates,” says Miriam Rotkin-Ellman, a senior scientist at the NRDC. “This is a real troubling trend,” she adds, noting that the EPA also recently downgraded the risks of the organophosphate pesticide acephate to children in a revised assessment.

The EPA is evaluating the safety of 18 organophosphate pesticides as part of a review process that occurs every 15 years. The agency is accepting comments on its proposed decision for TCVP until Nov. 20.



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